Machine for sizing bushings



Feb. 26, 1952 J. HALLAl-:R MACHINE FOR sIziNG BUsHINGs 2 SHEETS-SHEET AlFiled April 25. 1947 MQ mm. mm. NQ

Feb. 26, 1952 J ':||A| LER MACHINE FOR SIZING BUSHINGS 2 SHEETS-Smm 2Filed April 25. 194'?V n wa N ww W A z ff/ZI,

fw -I Patented Feb. 26, 1952 UNITED STATES PATENT OFFICE MACHINE FORSIZIN G BUSHINGS John Haller, Northville, Mich.

Application April 25, 1947, Serial No. 743,875

s claims..

This invention relates to fluid-operated presses,

and in particular to presses for shaping articles to their proper sizes.

One objectof this invention is to provide a sizing press to overcomedimensional variations arising in the manufacture of bushings preparedby powder metallurgy so as to bring the bushings to their intendeddimensions after they have been subjected' to the sintering operation.

Another object is to provide a sizing press for bushings prepared bypowder metallurg-y, as set forth in the preceding object, wherein thevarious elements of the press `operate automatically in timedrelationship to carry out the various steps in the bushing sizing cycleof operations.

Another object is to provide a sizing press for bushings prepared bypowder metallurgy, as set forth in the preceding objects, wherein themotions of the various elements of the press are started and stoppedaccording to a predetermined sequence of operations by means of limitswitches and a pressure-operated switch, so that the machine issubstantially automatic in its operation after it has once been started.

Another object is to provide a sizing press for bushings prepared bypowder metallurgy, as set forth in the preceding objects, wherein thebushings are fed automatically to the press, forced automatically into asizing die, sized for ther internal and external dimensions, andautomatically ejected from the die, after which the various elements ofthe press are then returned automatically to their start positionspreparatory to.

carrying out a new sizing operation upon the next bushing.

In the drawings:

Figure 1 is a central vertical section, partly in side elevation,through a fluid pressure press for sizing bushings, together with theelectric and hydraulic circuits therefor according to a preferred formof the invention;

Figure 2 is a central longitudinal section through one of the four-wayvalves used in the hydraulic circuit shown in Figure l;

Figure 3 is a vertical cross-section taken along the line 3 3 in Figure1, showing the bushingfeeding chute and sizing die;

Figure 4 is a diagrammatic longitudinal section through the principalWorking elements of the press of Figure 1 in their startingI position;

Figure 5 is a longitudinal section similar to Figure 4, but showing thepositions of the parts after the abutment plunger has moved intoengagement with the sizing die;

Figure 8 is a longitudinal section, similar to Figures 4 and 5, butshowing the positions of theY parts after the bushing has been forcedinto theA sizing die to properly size the outer dimensionA thereof;

Figure 7 is a view similar to Figures 4, 5 and 6, but showing thepositions of the parts after the internal sizing plunger has been movedthrough the bushing to properly size the internal bore thereof;

Figure 8 is a View similar to Figures 4 to 7 inelusive, but showing thepositions of the parts after the abutment plunger has been retracted cand the bushing pushed out of the sizing die; and

Figure 9 is a View similar to Figures 4 to 8 inclusive, but showing thepositions of the parts after the internal sizing plunger has beenretracted and the nished .bushing is being ejected.

Hitherto, the making of .bushings by powder metallurgy has been subjectto considerable difculty because of the great deviationsfrom theirintended dimensions during manufacture. Even though the formation -ofthe bushings is verycarefully controlled, after the sintering operationhas been carried out, such bushings are frequently found to deviate veryWidely from their desired dimensions. In order to use such bushingsproperly for bearing purposes, it is, of course, necessarythat theyshould very accurately t the shafts which they are used to support andat the same time provide very accurate clearances. rlhe purpose of thepresent machine is to restore such bushings to their proper dimensions,since these bushings by reason of their material and pecularities ofconstruction are capable of deformation into their proper dimensions.

Mechanical construction of press Referring to the drawings in detail,Figure l'l shows diagrammatically a bushing sizing press, generallydesignated Il), in longitudinal vertical section, together with thehydraulic circuit for and i6 therein for receiving a tubular die IT.'

The die Il has an internal bore I8 which is of precisely the desiredoutside diameter for thel iinished bushings. The die I'I is held inposition within the bore I5 by a retainingring I 9= secured thereto asat 20, and fitting into anI annular external recess 2 I vin the die I8.

The bushings 22 to be sized by the press of the4 present invention are,'as previously stated, made by powder metallurgy and, after sintering,are

placed in an inclined feed chute 23 (Figure 3) mounted on a bracket 24secured as at 25 to the die holder I2. The chute 23 is provided with aoor 26 which is extended downward below the lower end 21 of the chuteand terminates in a curved rest 28 which has a flared forward edge 29.

Likewise mounted on the base or bed and bolted thereto as at 3| is anabutment cylinder 32 having a bore 33 in which is reciprocably mounted aplunger 34 having a head 35 (Figure l) The plunger 34 passes through abore 36 in the end wall of the cylinder 32 and carries on its outer endan enlargement 31 with a socket 38 therein.

Mounted in the socket 38 and secured to the enlargement 31 by the bolt39 is an annular abutment 40 having a tubular recess 4| therein and anannular abutment portion 42 thereon.

The cylinder 32 in its side wall is provided with spaced fluid ports 43and 44 which are hydraulically connected, as set forth below. A cylinderhead 45 is bolted as at 46 to the abutment cylinder 32.

Mounted on the base or bed |I on the opposite side of the die holder I2from the abutment cylinder 32 and bolted thereto as at 41, is a sizingcylinder 48. The sizing cylinder 43 is provided with a bore 49 withinwhich a hollow outer plunger 50 reciprocates, access to the cylinderbore 49 being provided by ports 5| and 52 (Figure 1) connected to thehydraulic system as described below. The outer cylinder 48 is closed atits outer end by a cylinder head 53 bolted thereto as at 54 andcontaining the central axial bore 55. Similarly, the opposite end wallof the cylinder 48 is provided with an axial bore 55.

The plunger 5|) is provided with a hollow head 51 having an annularrecess 58 in one end wall thereof into which the enlarged end of thehollow plunger rod 59 snugly ts and is held in position by a retainingring 60 bolted as at 6I to the head 51. The hollow rod 50 in turn isprovided with an annular recess 62 in which is secured the enlarged endof an outer sizing plunger 63 of tubular form, and held in position by aretaining ring 64 bolted thereto as at 65. The outer sizing plunger 63is provided with an annular abutment face or end 56 of approximately thesame size as the ends of the bushings 22 to be sized. The

provision of the recess 62 and retaining ring 64 enables the outersizing plunger 63 to be removed and other plungers of dii-ferent sizesinserted, according to the diferent sizes of bushings 22 to be sized.

The outer sizing plunger 63 is provided with a longitudinal bore 61(Figure l) of substantially the same size as the inner bore of thebushing 22 to be sized and containing an inner sizing plunger 68 of thesame outer diameter as the inner diameter intended for the bushings 22.The plunger 68 passes through a bore 69 in the end of the hollow plungerrod 59 and is seated in a recess 10 in the end of a screw plug 1|, towhich it is secured by a fastener 12 threaded into the end thereof. Thescrew plug 1| in turn is threaded into a recess 13 in the end of aninner plunger 14 which is reciprocably mounted in the bore 15 within thehollow plunger rod 59 and which is provided with a head 16 which is inturn reciprocable in the enlarged bore 11 within the hollow head 51. Y

The head 16 and plunger 14 are provided with an axial bore 18 and apassageway 19 leading therefrom (Figure l) to the bore 11. Mounted inthe bore 18 is a tubular stem 89 having a longitudinal passageway 8|leading therethrough to a port 82. The stem 89 is provided with a threadenlargement 83 which is threaded into the outer end of a hollow plunger84. The inner end of the plunger 84 is enlarged as at 85 and is threadedinto the outer end of the bore 'l1 so as to form a closure therefor. Thehollow plungers 84 and 59 reciprocate to and fro within the bores 55 and56 respectively. The annular passageway 86 within the hollow plunger 34and outside the tubular stem 89 leads to a port 81 (Figure l).

Hydraulic system In order to reciprocate the various plungers, thecylinders containing these plungers are connected to three conventionalsolenoidally operated four-way valves, generally designated 83, 39 and90V respectively. Each of these valves is of any suitable type, and mayconsist of the type shown for purposes of illustration in Figure 2. Thevalve 88, for example, may consist of a valve casing 9| (Figure 2)containing a longitudinal bore 92 with annular enlargements 93 and 94near the opposite ends thereof and interconnected by a passageway in thewall thereof. The passageway 95 terminates in an exhaust port 91 leadingto a fluid supply tank, as described below. Diametrically opposite theexhaust port 91 is a pressure fluid supply port 99. On either side ofthe pressure fluid supply port 96 are ports 99 and 99 which arecustomarily piped to the opposite ends of the cylinder containing aplunger which it is desired to reciprocate in opposite directions. Theseports 98, 99 alternately serve as pressure and suction portsrespectively as the plunger is reciprocated in opposite directions.

Reciprocably mounted in the bore 92 is a valve spool lili] having threespaced heads 59|, |92 and |93 separated by neck portions |94 and |05.The valve spool |99 is also provided with a longitudinal passageway |06having transverse central and end passageways |01. The valve spool |98is connected at its opposite ends to operating rods |98 and |09 aroundwhich are cciled compression springs ||0 adapted to urge the valve spool|99 into its neutral position (Figure 2) when neither of the rods |98 or|99 is pushed or pulled.

The operation of the conventional four-way valve shown in Figure 2depends on the setting of the valve spool |09 as determined by theoperating rods |98 or |09. These are sometimes operated manually, but inthe present circuit are preferably operated by solenoids, as describedin connection with the electrical circuit. When the valve spool isshifted to the left, pressure iiuid passes from the port 96 into theport 98 and thence to the cylinder to be operated. Meanwhile, the fluiddischarged from the opposite end of that cylinder passes through theport 99 and passageways |01, |86 and 95 out through the discharge port91 to the tank.

When the spool |83 is shifted toward the righthand end of the bore 92(Figure 2) the reverse distribution of uid occurs. Under thesecircumstances, pressure fiuid is supplied from the port 96 through theneck portion |95 into the port 99 and thence to the cylinder beingoperated. The fluid displaced by the plunger thereof returns through theport 98 the passageways |91, |96 and 95 and the port 91 and returns tothe fluid supply tank.

The ports 43 and 44 of the abutment cylinder 32 are connected byconduits ||8 and to the four-way valve 88, whereas the ports 5| and 52of the outer bore 49 of the sizing cylinder 48 are connected by conduits||2 and ||3 to the four-1v way valve 89 (Figure 1). The ports 82 and 81connected to the hollow plungers or stem passageways 8| and 88respectively are connected by conduits ||4 and I I5 to the four-wayvalve l9|). The conduits just described are connected to ports in thefour-way valves 88, 89 and 90 corresponding to the ports 99 and 98 inFigure 2. The pressure uid for actuating the machine is sup` plied by ahydraulic pump IIB. the pressure side or outlet of which is connected bythe conduit I I 1 to the ports in the four-way valves 88, 89 and 98corresponding to the ports 96 in Figure 2. The suction port of the pump||6 is connected. by a conduit I I8 to the fluid tank I I9 upon whichthe pump I I6 is conveniently mounted. An electric motor coupled to thedrive shaft |2| of the pump I I6 operates the latter. ports of thefour-way valves 88, 89 and 99 corresponding to the port 91 of Figure 2are connected to the conduit |22 leading back to the luidvtank II9. Thelatter is lled with a suitable operating fluid, such as oil or water.The conduit I I5 is connected by a branch conduit |23 to a pres-lsure-responsive switch, generally designated |24 the discharge of whichis connected by the conduit |25 tothe conduit |22.

Electrical control system In order to actuate the four-way valves 88, 89and 90, each of these is provided with solenoid windings. The four-wayvalve v88 has solenoid: windings |26 and |21 (Figure l) adapted to shiftsolenoid armatures |28 and |29 on the endsV oi the control rods |08 and|99 respectively (Figure 2). Similarly, the four-way valve 89 isprovided with solenoid windings I 3|) and |3| adapted to actuate thecontrol rod armatures |32 and` |33 and the four-way valve 90 hassolenoid windings |34 and |35 operating the control rod armatures I 36and |31. trolled by a manual switch |48, limit switches |4I, |42, |43and |44, and by the pressure switch |24, as described hereinafter inconnection with the operation of the invention. The limitY switches |4I,|42, |43 and I 44 are supported respectively on brackets |45, |46, |41and |48 mounted respectively upon the cylinder 32, .die holder I2 andcylinder 48. The limit switch I4| is tripped by a projection 49 upon anarm |59 mounted upon an upright |5| which in turn is mounted upon theenlargement 31 of the plunger 34. The arm |58 also has'an end portion|53 which actuates the limit switch |42. The limit switches |43 and |44are actuated by a projection. |53 and an end portion |54 on an arm |55supported by an upright |56 mounted upon the hollow plunger rod 59.

The limit switches |4| and |42 are singlethrow normally open switcheswhereas the limit switches |43 and |44 are double-throw switches. All ofthe switches |4| and |44 are inter-connected by wiring which isenergized from asuitable source of electric current. In order tosimplify the wiring diagram, the points indicated by the black dots I 51to |66 inclusive are assumed to be interconnected and in turn to beconnected to a source of electric current.

Operation In the operation of the invention, let it be assumed that thevarious parts of the machine are in the position shown in Figures l and4. Let it also be assumed that a supply of bushings 22 The discharge Thesolenoid windings are con# to be sized has been placed in the chute 23,as shown in Figures 1 and 3, with the lower-most bushing 22 supportedupon the rest 28. The manual switch |48 is now closed by the operator,energizing-the forward solenoid coil |21 of the four-way valve 88 by wayof the left-hand contacts of the limit switch |44, which at this timeare -bridged by the switch bar. This action shifts the four-way valve 88to its forward stroke po sition, so as to admit pressure fluid from theline ||1 to the line III and port 44 at the left-hand end of thecylinder bore 33. This pressure uid pushes the plunger head 35, rod 34and annular abutment 48 to the right until the annular abutment surface42 engages the left-hand end oi the die I1. The iiuid escaping from therighthand end of the cylinder 32 escapes through the port 43, conduit||0, valve 88 and conduit |22 back to the tank H9. The parts have nowreached the positions shown in Figure 5. Mean# while, the switch bar ofthe limit switch |4| has.

rolled ofi the projection |49 as the arm |50 has moved to the right,opening its contacts and deenergizing the switch |4I.

When the annular abutment 4|J has reachedA the end of its travel, theend |52 of the arm |50 trips the limit switch |42, closing its contactsand thereby energizing the solenoid I3I of the four-way Valve 89. Thiscauses pressure uid to flow from the conduit |I1 into the conduit ||2and port 5| into the space immediately adjacent the cylinder head 53 ofthe cylinder 48. This pressure -forces the outer plunger 58 to the left,causing the outer sizing plunger 63 to engage the lowermost bushing 22and lpush it into'the bore I8 of the sizing die I1. Meanwhile, the uidescaping from the forward end of the cylinder bore 49 returns to thetank I I9 by way of the port 52, conduit ||3, valve 89 and conduitV II2.

The parts have now reached the positions shown' switch |44 as the end|54 of the arin |55 travels leftward.

The bridging of the right-hand contacts of the limit switch |43energizes the solenoid winding |35 of the four-way valve 99, shifting itto forward stroke. Pressure fluid is then delivered through the conduitII5 to the right hand end of the cylinder bore 11, shifting the plungerhead 16 and inner sizing plunger 68 to the left, causing the latter toenter the bore of the bushing 22. Meanwhile, the fluid displaced fromthe left-hand side of the head 16 escapes back to the tank ||9 f by wayof the stem 86, conduit II4, valve 90 and.

conduit |22. The parts have now reached the positions shown in Figure'1.

With the various plungers halted in engage-l ment with the bushing 22,the pump |15 conltinues to deliver pressure fluid thereto and thepressure rises in the hydraulic circuitl until it closesl the normallyopen pressure switch |24. This energizes the return solenoid winding I26 of the four-way valve 88, shifting it upon return stroke and causingthe flow-of pressureluid to accesar the cylinder bore 33 to be reversed,thereby retracting the abutment plunger 34. At. the same time theclosing. of the pressure switch. |24 also bridges. its left-hand pair ofcontacts so as to re-energize the forward solenoid winding I3I. of thefour-way switch 39, shifting this to forward stroke. This deliverspressure fluid through. the conduit H2 to cause the plunger head 85 andplunger rods 59 and 53 to move to the left, expelling the bushing 22from the sizing die as the abutment plunger 34 is retracted. The parts'-have now reached the positions shown in Figure 8.

As the abutment plunger 34 is retracted to the position shown in Figurel, the-,projection |49 on the arm, I5i| closes thenormally-open limitswitch MI, thereby energizing the return solenoid windings |3ll and |34ofthe four-way valves 89 and 90., shifting these valves to return strokepositions. This causes pressure fluid to be delivered through theconduits 3 and i4, retracting the outer and inner plungers. 59 and 14and also the sizing plungers 63 and til.v The parts have now reached theposiitons shown in Figure 9, and the bushing.. thus ejected by theretraction of the plungers 63 and 68, drops into a suitable receiver.Meanwhile,l another bushing 22 drops from the chute 23 onto the rest 28.

The retraction of the plunger 59 causes the. end |54 of the arm |55 totrip the limit switch |44 so as to unbridge its right-hand contacts andbridge itsleft-hand contacts, as shown in Figure l. This cle-energizesthe. return solenoid windings. |30 and |34 of the four-Way valves 89and. S0, shifting them to their neutral positions and halting theretraction of the plungers 58 and '14. The bridging of the left-hand,contacts ofA the. limit switch |44, however, starts the. cycle ofopera-` tions anew by re-energizing the forward solenoid winding |21 ofthe. four-way valve 88 shifting it to forward stroke position. Assumingthat the manual switch |40 is still closed, the. above described cycleof operations repeats itself indefinitely as long as bushings 22 aresupplied. to thechute 23 to be sized.

What I claim is:

l. In combination in a bushing sizing: appara.- tus, an external bushingsizingY member having a sizing bore therein open at both ends withA itsin-- ternal` diameter slightly smaller than the external, diameter ofthe, bushing to be sized fory receivingA said bushing, a movableabutment mem ber engageable with one end of said external sizing member,a bushing feeding member of smaller diameter than said bore engageablewith one end of said bushing to feed said bushing into.` said sizingbore, an internal bushing. sizing member of the internal diameterdesired for said bushing, engageable with the interior of saidbushing,fluid pressure motors connected to said abutmentmember and to saidfeeding member and to said internal sizing member, a source ofpressureiuid1 connected to said motors, av duid pressure controlcircuitv including a conduit system. connecting said motors to saidfluid pressure source and containing control valves operable in timedrelation ship to move said abutment member into. engagement with one endof said sizingA member and to move said feeding member toward the. otherend of said external sizing member to. feed said bushing into said bore,and tozmove saidY internal sizing member into said bushing and a.pressure-responsive. device operableto retract' said abutment memberand. to further advance said feeding member through said bore to eject8,-. said bushing from said bore in response to the attainment. of apredetermined pressure in said circuit.

2. In combination in a. bushing sizing apparatus, an external bushingsizing member having a sizing bore therein open at both ends with itsinternal` diameter slightly smaller than the external diameter of thebushing to be sized` for receiving said bushing, a movable abutmentmember engageable with one end of said external sizing member, a bushingfeeding member of smaller diameter than said bore engageable with oneend of said bushing to feed said bushing into said sizing bore, aninternal bushing sizing member of the internal diameter desired for saidbushing engageable with the interior ofl said bushing, fluid pressuremotors connected to said abutment member and to said feeding member andto said internal sizing member, a source of pressure fluid connected tosaid motors, a uid pressure control circuit including a conduit systemconnecting said motors to said fluid pressure source and containingcontrol valves operable in timed relationship to move said abutmentmember into engagement with one end of said sizing member and to movesaid feeding member toward the other end of said external sizing memberto.` feeding said bushing into said bore, and to move said internalsizing member into said bushing and a pressure-responsive deviceoperable to retract said abutment member and to further advance saidfeeding member through said bore to eject,

said bushing from said bore and withdraw said internal sizing memberfrom said bushing in response to the attainment of a predeterminedpressure in said circuit.

3. 1n combination in a bushing sizing apparatus, an external bushingsizing member having a sizing bore therein open at both ends with its.internal diameter slightly smaller than they external diameter of thebushing tol be sized for receiving said bushings a movable abutmentmember engageable with one end of said external sizing member, a,bushing feeding member of smaller diameter than said bore engageablewith one. end of said bushing to feed said bushing; into. said sizingbore, an internal bushing sizing member of the internal diameter desiredfor said bushing engageable with the interior of said bushing, fluid,pressure motors connected to. said abutment member and to said feedingmember and to said internal sizing member. a source. of pressure. fluidconnected to said motors, and aV fluid pressure control circuitincluding a conduit system connecting said motors to said fluid pressuresource and 'containingcontrol valves operable. in timed relationship tomove said abutment member into engagement with one end of said sizingmember and to move said feeding member toward the other end of saidexternal sizing member to feed said bushing into saidbore, and to movesaid internal sizing member into said bushing and thereafter to retractsaid abutment member and to further advance said feeding member throughsaid bore to eject saidbushing from said bore.

4. In combination in a bushing sizingapparatus, a sizing die having asizing bore therein open at both ends with its internal diameterslightly smaller than the external diameter of the bushing to be sizedforA receiving said bushing, a. iiuid-pressure-operated abutment plungermovable into engagement with one end ofA said die, auid-pressure-operated feeding plunger of: smaller diameter than saidboreengageable with one end of said bushing to feed said bushing into saidbore, a huid-pressure-operated internal sizing plunger of the internaldiameter desired for said bushing movable into the interior of saidbushing, a source of pressure iiuid, a fluid pressure circuit connectingsaid source of pressure fluid to said plungers, a fluid pressure controlcircuit including a conduit system connecting said motors to said fluidpressure source and containcontrol valves operable in timed relationshipto move said abutment plunger into engagement with one end of said dieand also to move said feeding plunger toward said die to feed saidbushing into said bore and iinally to move said internal sizing plungerinto said bushing vand a pressure responsive device operable in responseto the attainment of a predetermined pressure in said iiuid pressurecircuit to retract said abutment plunger and to further advance saidfeeding plunger through said bore to eject said bushing from said bore.

5. In combination in a bushing sizing apparatus, a sizing die having asizing bore therein open at both ends with its internal diameterslightly smaller than the external diameter of the bushing to be sizedfor receiving said bushing, a -luid-pressure-operated abutment plungermovable into engagement with one end of said die, afiuid-pressure-operated feeding plunger of smaller diameter than saidbore engageable with one end of said bushing to feed said bushing intosaid bore, a uid-pressure-operated internal sizing plunger of theinternal diameter desired for said bushing movable into the interior ofsaid bushing, a source of pressure iiuid, a uid pressure circuitincluding a conduit system connecting said source of pressure iiuid tosaid plungers, a pressure fluid control valve in said conduit systemconnected between said source and 'each of said plungers, an electricalvalve operator connected to each valve, and an electrical controlcircuit interconnecting said operators, said electrical control circuitincluding a pressure responsive switch operable in response to theattainment of a predetermined pressure in said fluid pressure circuit toenergize certain of said operators to retract said abutment plunger andto further advance said feeding plunger through said bore to eject saidbushing from said die.

6. A bushing sizing press comprising a supporting structure, a dieholder mounted on said structure, an external bushing sizing die mountedon said die holder and having a bore therethrough open at both ends withits internal diameter slightly smaller than the external diameter o1'the bushing to be sized and adapted to receive said bushing, a pluralityof iiuid pressure motors mounted on said structure on opposite sides ofsaid die holder, an annular abutment member mounted on one motor andhaving a bushing feeding member receiving socket, said abutment 1'member being disposed in alignment with said die and movable into andout of closing engagement with one end of said bore, a bushing feedingmember of smaller diameter than said bore mounted on one-motor andmovable through said bore from the opposite end thereof and an internalbushing sizing member of the internal diameter desired for said bushingmounted upon one motor and movableinto and out of said bushing.

7. A bushing sizing press comprising a supporting structure, a dieholder mounted on said structure, an external bushing sizing die mountedon said die holder and having a bore therethrough open at both ends withits internal diameter slightly smaller than the external diameter of thebushing to be sized and adapted to receive said bushing, a plurality ofiluid pressure motors mounted on said structure on opposite sides ofsaid die holder, an annular abutment member mounted on one Imotor andhaving a bushing feeding member receiving socket, said abutment memberbeing disposed in alignment with said die and movable into and out ofclosing engagement with one end oi said bore, a bushing feeding memberof smaller diameter than said bore mounted on one motor and 'movablethrough said bore from the opposite end thereof, an internal bushingsizing member of the internal diameter desired for said bushing mountedupon one motor and movable into and out of said bushing and a. bushingholder adapted to contain a multiplicity of bushings and having abushing rest at its outlet mounted adjacent said die and positioned tohold a bushing in alignment with said bore and said feeding member.

8, A bushing sizing press comprising a supporting structure, a dieholder lmounted on said structure, an external bushing sizing diemounted on said die holder and having a sizing bore therethrough open atboth ends with its internal diameter slightly smaller than the externaldiameter of the bushing to be sized and adapted to receive said bushing,a fluid-pressure-operated annular abutment plunger having a sizingplunger receiving socket therein, said abutment plunger being movableinto and out of engagement with one end of said die, and telescopingfeeding and internal sizing plungers movable toward and away from saiddie and into engagement with said bushing to push said bushing into saiddie and insert said sizing plunger in said bushing, said feeding plungerhaving an external diameter smaller than the minimum internal diameteroi' said sizing bore.

JOHN HALLER.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STA-TES PATENTS

